Homalolides C-D, two new sesquiterpenoids from the rhizomes of Homalomena pendula.

Two new sesquiterpenoids, homalolides C - D (1‒2), were co-isolated from the rhizomes of Homalomena pendula (Blume) Bakh.f collected in Vietnam with five known ones, aromadendrane-4α,10α-diol (3), bullatantriol (4), 1ß,4ß,6α-trihydroxy-eudesmane (5), 1ß,4ß,6ß-trihydroxyeudesmane (6), and 1ß,4ß,7α-trihydroxy-eudesmane (7). The structures and relative configuration of new compounds were elucidated by 1 D-/2D-NMR, IR, UV and HRESIMS analyses, and by comparisons to the reported data in the literature. Homalolide C presented an unprecedented skeleton with the 4/8 bicyclic system. All isolates did not exhibit appreciable inhibitory effects on LPS-induced NO production in the RAW 264.7 macrophage cell line and on the growth of human lung cancer cell line (SK-LU-1).

Eudesmane-type sesquiterpenoids from the aerial parts of Artemisia lavandulaefolia and their anti-pancreatic cancer activities.

Five undescribed eudesmane sesquiterpenoids, artemilavanins A-E, and one undescribed rearranged eudesmane sesquiterpenoid, artemilavanin F, were isolated from the 95% ethanol extract of the aerial parts of Artemisia lavandulaefolia DC., along with ten known compounds. The structures and configurations of undescribed compounds were mainly elucidated by spectroscopic analyses and single-crystal X-ray diffraction analysis. Among all isolated compounds, artemilavanin F exhibited inhibitory activity on PANC-1 pancreatic cancer cells with IC50 of 9.69 ± 2.39 µM. Artemilavanin F inhibited PANC-1 cell proliferation by induction of G2/M cell cycle arrest and apoptosis mediated by downregulation of cyclin-dependent kinases and accumulation of reactive oxygen species. Moreover, artemilavanin F inhibited the colony formation, cell migration and sphere formation of PANC-1 cells, indicating the suppression of stem-cell-like phenotype of PANC-1 cells. Further results confirmed that the expression of cancer stem cell markers such as Bmi1, CD44, CD133 were inhibited by artemilavanin F. Downregulation of epithelial-mesenchymal transition (EMT) markers such as N-cadherin and Oct-4 indicated the potential of artemilavanin F in prevention of metastasis.

Eudesmane-type sesquiterpenes from the rhizomes of Atractylodes macrocephala and their bioactivities.

Fifteen undescribed eudesmane-type sesquiterpenes, named atramacronoids D-R, along with fourteen known analogues were isolated from the rhizomes of Atractylodes macrocephala. The structures of atramacronoids D-R were elucidated based on extensive spectroscopic data analysis, Snatzke's rule, electronic circular dichroism (ECD) calculations, and X-ray crystallographic analysis. Notably, of the undescribed isolates, atramacronoids D and E are the first example of eudesmanolactam-phenol and eudesmanolactam-ethyl hybrids obtained from plants, respectively. A pair of enantiomers, (+)- and (-)-atramacronoids F, were successfully resolved by chiral-phase HPLC. Atramacronoid D exhibited weak cytotoxicity against SGC-7901 cells. Atramacronoid E significantly promoted the proliferation of LPS-induced IEC-6 cells.

Two new eudesmane sesquiterpene glucosides from the aerial parts of Artemisia vulgaris.

Using combined chromatographic methods, two new sesquiterpene glucosides, vulgarosides A (1) and B (2), and two known analogs ainsliaside E (3) and pumilaside A (4) were isolated from the aerial parts of Artemisia vulgaris. Their chemical structures were established by spectroscopic methods, including one and two-dimensional nuclear magnetic resonance (1 D and 2 D-NMR) spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). In addition, their cytotoxicity on five human cancer cell lines, including KB (epidermoid carcinoma), HepG2 (hepatocarcinoma), MCF7 (breast carcinoma), SK-Mel-2 (melanoma), and LNCaP (prostate cancer) was also evaluated by the SRB assay. However, none of the tested eudesmane sesquiterpene glycosides showed significant cytotoxicity (IC50>100 µM).

Polyhydroxylated eudesmane sesquiterpenoids and sesquiterpenoid glucoside from the flower buds of Tussilago farfara.

Chemical fractionation of the n-BuOH partition, which was generated from the EtOH extract of the flower buds of Tussilago farfara, afforded a series of polar constituents including four new sesquiterpenoids (1-4), one new sesquiterpenoid glucoside (5) and one known analogue (6) of the eudesmane type, as well as five known quinic acid derivatives (7-11). Structures of the new compounds were unambiguously characterized by detailed spectroscopic analyses, with their absolute configurations being established by X-ray crystallography, electronic circular dichroism (ECD) calculation and induced ECD experiments. The inhibitory effect of all the isolates against LPS-induced NO production in murine RAW264.7 macrophages was evaluated, with isochlorogenic acid A (7) showing significant inhibitory activity.

[New eudesmane sesquiterpenoids from Atractylodis Macrocephalae Rhizoma and their inhibitory activities against SREBPs].

Three sesquiterpenoids were isolated and purified from the 95% ethanol extract of Atractylodis Macrocephalae Rhizoma by column chromatography on silica gel, Sephadex LH-20, ODS, and high-performance liquid chromatography(HPLC). Their chemical structures were identified on the basis of spectroscopic analysis and physiochemical properties as(7Z)-8ß,13-diacetoxy-eudesma-4(15),7(11)-diene(1), 7-oxo-7,8-secoeudesma-4(15),11-dien-8-oic acid(2), and guai-10(14)-en-11-ol(3). Compounds 1 and 2 are new compounds and compound 3 was obtained from Compositae family for the first time. Compounds 1, 2, and 3 showed weak inhibitory activities against sterol regulatory element-binding proteins(SREBPs).

Simultaneous determination of asarinin, ß-eudesmol, and wogonin in rats using ultraperformance liquid chromatography-tandem mass spectrometry and its application to pharmacokinetic studies following administration of standards and Gumiganghwal-tang.

Asarinin, ß-eudesmol, and wogonin have common antiangiogenic activities and have the potential for use in chemotherapy. Besides, they are multivalent substances that are combined in various herbal medicines. The purpose of this study was to develop a method for simultaneous analysis of asarinin, ß-eudesmol, and wogonin, which are representative pharmacological components of Asarum heterotropoides, Atractylodes lancea, and Scutellaria baicalensis, respectively, in rat biosamples using ultraperformance liquid chromatography-tandem mass spectrometry. The three components were separated using 5 mm aqueous ammonium acetate containing 0.1% formic acid and acetonitrile as a mobile phase, equipped with a KINETEX core-shell C18 column. The analysis was quantitated on a triple-quadrupole mass-spectrometer employing electrospray ionization, and operated in the multiple reaction monitoring mode. The chromatograms showed high resolution, sensitivity, and selectivity with no interference with plasma, urine, and feces constituents. The developed analytical method satisfied international guidance criteria and could be successfully applied to the pharmacokinetic (PK) studies evaluating oral bioavailability of asarinin, ß-eudesmol, and wogonin after oral and intravenous administration and their urinary and fecal excretion ratios after oral administration to rats. Furthermore, the analysis was extended to PK studies following oral administration of Gumiganghwal-tang. This study was the first simultaneous analysis of the aforesaid three constituents in rat plasma, urine, and feces that also determined their PK parameters.

Two new eudesman-4α-ol epoxides from the stem essential oil of Laggera pterodonta from Côte d'Ivoire.

The investigation of the stem essential oil of Laggera pterodonta (DC.) Sch. Bip. ex Oliv. (Asteraceae) from Côte d'Ivoire was carried out, using a combination of chromatographic (GC-RI, CC, pc-GC) and spectroscopic (GC-MS, 13C NMR) techniques. This study led to the identification of fifty constituents of which two new natural compounds 7ß,11ß-epoxy-eudesman-4α-ol and 7α,11α-epoxy-eudesman-4α-ol. Their structures were elucidated by 1 D and 2 D NMR spectroscopy after pc-GC purifying. Finally, 98.9% of the whole composition of the oil was identified with a high amount of 2,5-dimethoxy-p-cymene (78.9%). The other significant components were α-humulene (6.2%), (E)-ß-caryophyllene (1.7%), thymyl methyl oxide (1.7%), α-phellandrene (1.5%), p-cymene (1.2%), (3αH,4ßH,6αH,1αMe)-1,6-epoxy-3-hydroxycarvotanacetone angelic acid ester (1.1%) and 10-epi-γ-eudesmol (1.0%).

Microscopic Characteristic and Chemical Composition Analysis of Three Medicinal Plants and Surface Frosts.

The accumulation of chemical constituents of some medicinal plants, such as Paeonia ostii T. Hong et J. X. Zhang, Houpoëa officinalis (Rehder and E. H. Wilson) N. H. Xia and C. Y. Wu. and Atractylodes lancea (Thunb.) DC, can precipitate on the surface and form frosts after natural or artificial intervention. The characteristics of these three medicinal plants and their frosts were analyzed by light microscope, polarizing microscope, stereomicroscope, and metalloscope. The results of ordinary Raman of P. ostii and H. officinalis showed that the frosts of P. ostii matched paeonol, while that of H. officinalis matched magnolol and honokiol. In P. ostii and its frost, 19 peaks were identified by UPLC-Q/TOF-MS, and the main component was paeonol. Eleven components were identified in H. officinalis and its frosts, and the main components were magnolol and honokiol. A. lancea and its frosts were analyzed by gas chromatography-mass spectrometry (GC-MS), 21 were identified, and its main components were hinesol and ß-eudesmol. These three medicinal plants accumulate compounds and precipitate frosts on the surface. The results show that the components of the frosts provide a basis for quality evaluation and research on similar medicinal plants, and reveals the scientific connotation of "taking the medicinal materials' precipitated frosts as the best" of P. ostii, H. officinalis, and A. lancea, to some extent.

Structure elucidation and NMR assignment of two new eudesmane derivatives from Merremia yunnanensis.

Two new eudesmane derivatives, 1α,6ß,9ß-trihydroxy-eudesm-3-ene-1-O-ß-d-glucopyranoside (1) and 1α,6ß,9ß-trihydroxy-eudesm-3-ene-1-(6-cinnamoyl)-O-ß-d-glucopyranoside (2) were discovered from Merremia yunnanensis. The structures were elucidated by analysis of their spectroscopic data including HR-ESI-MS, 1D, and 2D NMR. It should be noted that this is the first report about structure elucidation and NMR assignment of compounds from M. yunnanensis.

Chemical composition of essential oil from plants of abandoned mining site of Elba island.

The essential oil composition of three spontaneous species growing in an abandoned mining of Elba island was analyzed by GC-MS. A total of 194 compounds were identified representing 73.7-100% of the whole oil composition. The essential oils of Cistus salvifolius and Dittrichia viscosa from this site showed different profiles in comparison with those from not polluted area, where oxygenated sesquiterpenes were the main class. Volatiles from D. viscosa growing in ex-mining area presented 10-epi-γ-eudesmol and α-eudesmol as main compounds while ß-caryophyllene and limonene were the main ones in not polluted area. Ambroxide and ambrial were the most important compounds in the essential oil from C. salvifolius harvested in polluted area while nonanal and tridecanal were the main compounds in control samples. Oxygenated monoterpenes were the most abundant class from both Lavandula stoechas samples, with fenchone and camphor as main compounds.

Chemical investigations of male and female leaf extracts from Schinus molle L.

The pepper-tree Schinus molle is an evergreen ornamental plant with various and diversified list of medical uses. In this article we analysed the chemical composition of male and female leaves of this plant during the off-flowering and flowering seasons. The leaf extracts were obtained by using a sequential extraction with solvents of different polarities and the chemical composition was investigated by GC-MS. The results showed a total of twenty-three components, in which elemol is the most abundant constituent followed by bicyclogermacrene, γ-eudesmol, α-eudesmol, ß-eudesmol and isocalamendiol. The petroleum ether and diethyl ether extracts from male and female flowering and off-flowering leaves consisted of sesquiterpene hydrocarbons as a major constituent followed by monoterpene hydrocarbons, while the acetone extracts showed a different composition. The obtained results show differences in the chemical composition between male and female and flowering and not flowering.

Chemical composition and α-amylase inhibitory activity of the essential oil from Sabina chinensis cv. Kaizuca leaves.

Sabina chinensis cv. Kaizuca (SCK) is a variant of S. chinensis L. The essential oil from its leaves exhibited α-amylase inhibitory activity in vitro and the IC50 value was 187.08 ± 0.56 µg/mL. Nineteen compounds were identified from this essential oil by gas chromatography-mass spectrometry (GC-MS) analysis. The major compounds identified were bornyl acetate (42.6%), elemol (20.5%), ß-myrcene (13.7%) and ß-linalool (4.0%). In order to study the reason of the α-amylase inhibitory activity of this essential oil, the identified compounds were docked with α-amylase by molecular docking individually. Among these compounds, γ-eudesmol exhibited the lowest binding energy (-6.73 kcal/mol), followed by α-copaen-11-ol (-6.66 kcal/mol), cubedol (-6.39 kcal/mol) and α-acorenol (-6.12 kcal/mol). The results indicated that these compounds were the active ingredients responsible for the α-amylase inhibitory activity of essential oil from SCK.

Metabolism and pharmacokinetics of alantolactone and isoalantolactone in rats: Thiol conjugation as a potential metabolic pathway.

Alantolactone (AL) and isoalantolactone (IAL), two major active sesquiterpene lactones isolated from Radix Inulae extract, have a wide range of pharmacological activities. The predominant metabolic pathway of AL and IAL observed was glutathione (GSH) conjugation in vitro, which could occur in the absence of metabolic enzymes. Non-enzymatic conjugation with cysteine (Cys) couldalso be observed. Four metabolites (AL-GSH, AL-Cys, IAL-GSH, IAL-Cys) were subsequently isolated and confirmed by nuclear magnetic resonance (NMR). The results indicated that the thiol of GSH or Cys can be reacted with the exomethylene carbon atoms of α, ß-unsaturated carbonyl of AL and IAL. After intravenous administration in rats, AL and IAL were extensively metabolized, and the exposure, as measured by area under the concentration-time curve (AUC), for AL-GSH, AL-Cys, IAL-GSH, and IAL-Cys was approximately 1.54-, 0.96-, 1.50-, and 0.91-fold that of the parent drug, respectively. The AUC ratio of metabolites to parent compounds of oral administration was 3.66-, 9.19-, 12.97-, and 9.92-fold that of the parent drug for the above metabolites, respectively. The bioavailability of AL-total (AL, AL-GSH, AL-Cys) and IAL-total (IAL, IAL-GSH, IAL-Cys) was, respectively, 8.39% and 13.07%, which was 3.62- and 6.95- fold that of AL (2.32%) and IAL (1.88%), respectively. The oral exposure will be underestimated if the parent drugs are tested alone. These findings provide useful information for preclinical safety evaluation, and for predicting AL and IAL metabolism in humans.

Silver perchlorate in the mobile phase for rapid separation and determination of a pair of positional isomers in Inula racemosa Hook.f. with RP-HPLC.

Alantolactone and isoalantolactone isolated from many species of plants are a pair of positional isomers of CC bond. Previously, alantolactone and isoalantolactone have been proved to be good lead compounds for future anticancer agent development. Similarity of their molecular structures increases the separation difficulty for these two isomers on a conventional C18 column. Silver perchlorate (AgClO4) as mobile phase additives with RP-HPLC for improving the separation was developed for rapid determination of the positional isomers in Inula racemosa Hook.f. The effects of the concentration of silver perchlorate on the separation of the analytes were investigated. The composition of acetonitrile and water containing 5.0% silver perchlorate in a 65:35 (v/v) ratio was used as mobile phase, in which they were well separated within a short period of time on the C18 column. The method was successfully applied to determine them in an extract of Inula racemosa Hook.f. root. Silver perchlorate in mobile phase can efficiently improve the separation of the positional isomers and could be applied to rapidly determinate their content in this plant.

Chemical composition and antioxidant activity of essential oil from leaves and rhizomes of Curcuma angustifolia Roxb.

The essential oil extracted from rhizome and leaf of Curcuma angustifolia Roxb. (Zingiberaceae) was characterised by gas chromatography-mass spectrometry (GC-MS). The GC-MS analysis revealed the presence of 32 and 35 identified constituents, comprising 92.6% and 92% of total leaf and rhizome oil, respectively. Curzerenone (33.2%), 14-hydroxy-δ-cadinene (18.6%) and γ-eudesmol acetate (7.3%) were the main components in leaf oil. In rhizome oil, curzerenone (72.6%), camphor (3.3%) and germacrone (3.3%) were found to be the major constituents. Antioxidant capacities of oil were assessed by various methods, 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and reducing power ability (RPA). Based on the results, the leaf oil showed more antioxidant potential as compared to rhizome oil and reference standards (ascorbic acid and butylated hydroxytoluene (BHT)). Thus, the leaf essential oil of C. angustifolia can be used as an alternative source of natural antioxidant.

Essential oil composition of Ajuga comata Stapf. from Southern Zagros, Iran.

The chemical composition of essential oil obtained from the aerial parts of Ajuga comata Stapf. was analyzed by GC and GC/MS. Thirty-seven components were identified in the oil. (E)-ß-caryophyllene (30.9%), caryophyllene oxide (24.9%), (E)-ß-farnesene (12.6%), ß-eudesmol (3.2%), δ-cadinene (3.1%) and germacrene D (3.0%) were the main compounds in the EOs. The chemical composition of A. comata Stapf. from the Southern Zagros of Iran is reported for the first time.

Chemical Composition and Bioactivity of Essential Oil of Atalantia guillauminii against Three Species Stored Product Insects.

The toxic and repellent activities of the essential oil extracted from the leaves of Atalantia guillauminii Swingle were evaluated against three stored product insects, red flour beetles (Tribolium castaneum), cigarette beetles (Lasioderma serricorne) and booklice (Liposcelis bostrychophila). The essential oil obtained by hydrodistillation was investigated by GC-MS. The main constituents of the essential oil were ß-thujene (27.18%), elemicin (15.03%), eudesma-3, 7(11)-diene (9.64%), followed by (-)-4-terpeniol (6.70%) and spathulenol (5.25%). The crude oil showed remarkable contact toxicity against T. castaneum, L. serricorne adults and L. bostrychophila with LD50 values of 17.11, 24.07 µg/adult and 55.83 µg/cm(2) respectively and it also displayed strong fumigant toxicity against T. castaneum, L. serricorne adults with LC50 values of 17.60 and 12.06 mg/L respectively, while weak fumigant toxicity against L. bostrychophila with a LC50 value of 16.75 mg/L. Moreover, the essential oil also exhibited the same level repellency against the three stored product insects, relative to the positive control, DEET. At the same concentrations, the essential oil was more repellent to T. castaneum than to L. serricorne. Thus, the essential oil of A. guillauminii may be potential to be developed as a new natural fumigant/repellent in the control of stored product insects.

Chemical composition and biological activity of the essential oil from Helichrysum microphyllum Cambess. ssp. tyrrhenicum Bacch., Brullo e Giusso growing in La Maddalena Archipelago, Sardinia.

Helichrysum microphyllum Cambess. subsp. tyrrhenicum Bacch., Brullo e Giusso (Asteraceae), previously known as Helichrysum italicum ssp. microphyllum (Willd.) Nyman, is one of the many endemic species growing in Sardinia, Corsica and Balearic Islands. In the present work the composition of the essential oil obtained from a population of H. microphyllum ssp. thyrrenicum growing in a littoral location of La Maddalena Archipelago was investigated by GC-FID and CG-MS. The major compounds of the oil were the monoterpene ester neryl acetate (18.2%), the oxygenated sesquiterpene 5-eudesmen-11-ol (rosifoliol, 11.3%), the sequiterpene hydrocarbons δ-cadinene (8.4%) and γ-cadinene (6.7%), showing a peculiar composition in comparison with other Sardinian populations. The oil was tested for cytotoxicity on three human tumor cell lines (MDA-MB 231, HCT116 and A375) by MTT assay showing a strong inhibitory activity on human malignant melanoma cells A375 (IC50 of 16 µg/ml). In addition the oil was assessed for antioxidant activity by DPPH and ABTS assay.

Simultaneous determination of chlorogenic acid, caffeic acid, alantolactone and isoalantolactone in Inula helenium by HPLC.

A rapid and sensitive high-performance liquid chromatographic (HPLC) method was developed for the simultaneous separation and determination of chlorogenic acid, caffeic acid, alantolactone and isoalantolactone in Inula helenium. The HPLC separation was performed on an Elite Hypersil C18 column (200 × 4.6 mm i.d., 5 µm particle size) with a gradient elution of solvent A (acetonitrile) and solvent B (0.1% phosphoric acid in water) at a flow rate of 1.0 mL/min. Detection was monitored at 225 nm. The recovery of chlorogenic acid ranged from 95.6 to 107.7%, the recovery of caffeic acid ranged from 95.4 to 104.2%, the recovery of alantolactone ranged from 95.8 to 100.8% and the recovery of isoalantolactone ranged from 96.5 to 102.3%. The retention times for chlorogenic acid, caffeic acid, alantolactone and isoalantolactone were 5.2, 7.1, 25.6 and 26.6 min with the limits of detection of 0.069, 0.021, 0.039 and 0.051 µg/mL, respectively. Relative standard deviation for the intra-day and inter-day was ≤2.5%. The validated method is reliable for the routine control of these four compounds in I. helenium.